Renegade Wizards. Tracy Hickman Presents the Anvil of Time

Before the War of the Lance, magic faced and fought its own demise. The Journeyman is charged to use the ancient Anvil of Time to travel back along the river of time and find the lost stories that fell between the pages of the history books. He finds Tythonnia, a young red robe learning magic in company with Ladonna of the black robes and Par-Salian of the white. The three are sent on an easy quest to find the leader of the renegade wizards, a man named Berthal, but if it was that simple, they wouldn't need mages.
Instead, what started out easy turns into betrayal - magic against sorcery, the wizards against each other, and Tythonnia against herself. When Berthal finally unleashes his final attack, everyone knows that it won't end that simply.